JPH0215897Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to a run-out prevention device when pulling out a sheet-like yarn from a beam.

Background of the invention When a sheet of yarn wound around a beam is pulled out using a sizing machine or other winding machine, once the final end of the yarn is pulled out from the beam, that is, in a run-out state, the tension of the yarn increases. The threads run out and become entangled with each other, damaging the reed and causing problems in subsequent work, such as pasting tape to align the threads. Therefore, it is necessary to stop the machine before runout.

Prior Art Normally, gluing machines and other winding machines are equipped with a preset length measuring counter. By setting a value less than or equal to the subtracted value as a preset value, the machine can be stopped before runout.

Another method is to insert colored paper or the like into the position where the stop signal is to be generated when winding the beam, and then when the beam is pulled out, the colored paper is ejected and stops the machine. ing. Detection of such colored paper may be done visually, but it may also be automated using an optical detector.

The disadvantage of the former method is that errors occur due to the expansion and contraction of the thread. In addition, both the former and latter methods require human work, such as understanding the winding length, setting preset values, and inserting colored paper, so errors in work and settings can occur, resulting in run-out. It cannot be completely prevented.

Purpose of the invention Therefore, the purpose of the present invention is to eliminate human error by eliminating human work in order to prevent run-out when pulling out sheet-like yarn from a beam.

Summary of the invention Therefore, the present invention uses two counters to accurately measure the winding diameter near the barrel diameter of the drawing beam based on the rotation ratio of the roller and the beam, and when the winding diameter approaches the barrel diameter, the machine automatically I am trying to stop it.

Principle of the invention First, the principle of the invention will be explained based on FIG.

A large number of sheet-shaped yarns, that is, a yarn sheet 1, are pulled out from a beam 3 wound around a barrel 2 and run at a speed equal to the circumferential speed of a pair of guiding rollers 4 of a winding machine. A pulse generator 5 connected to the roller 4 and a pulse generator 6 connected to the axis of the beam 3 each generate pulses proportional to their rotational speed.

If the pulse generator 6 generates the number n of pulses while the pulse generator 5 generates the number N of pulses, then the diameter Dn of the beam at that time can be calculated using the following formula (1) with K as the proportionality constant. It is represented by.

Dn=KN/n...(1) Similarly, when the barrel diameter of barrel 2 is Do, while one pulse generator 5 generates the number of pulses N, the other pulse generator 6 generates the number of pulses no. If so, number of pulses no> number of pulses n
The barrel diameter Do is expressed by the following equation (2).

Do=KN/no...(2) Winding diameter Dn and barrel diameter Do when detected here
The difference between ΔD and ΔD, that is, the thickness ΔD of the remaining wound yarn layer, is determined as follows using the above equations (1) and (2).

ΔD=Dn-Do=KN/n-KN/no =KN/no(no-n/n)=Dono-o/n...(3) Here, the number of pulses generated when the barrel diameter reaches Do is , and the number of pulses generated when the winding diameter Dn is Δn, it is expressed by the following equation (4).

Δn=no−n (Δn is a positive integer) (4) Based on this relationship, the above equation (3) can be rewritten as follows.

ΔD=DoΔn/no−Δn = Do/no・Δn/(1−Δn/n ₀ ) ……(5) Now, the present invention detects when the winding diameter Dn approaches the barrel diameter Do. Since this is the purpose, the pulse difference Δn is small. Furthermore, if the number of pulses no is set to be sufficiently large, the above equation (5)
becomes simple as below.

ΔD≒Do/no・Δn = Do/no(no−n) ……(6) In other words, if the number of pulses no is set sufficiently large when the barrel diameter Do is the minimum, the thread layer thickness ΔD will be It can be seen that it is proportional to (no-n) near the barrel diameter Do, and the proportionality constant at that time is Do/no. From these, the pulse difference Δn corresponding to the thickness ΔD of the thread layer is determined by equation (6), and the conditions under which the thickness ΔD of the thread layer is less than this are shown by the following equation (7).

n≧no−Δn ...(7) In the present invention, based on the above equation (7), the pulse generator 5 uses the number of pulses N to indicate that the thickness ΔD of the yarn layer of the remaining yarn has become less than a certain value. The number n of pulses from the pulse generator 6 is determined by equation (7) while the number of pulses is being generated, and the machine is automatically stopped based on the result.

In this way, the present invention detects the minute thickness ΔD of remaining yarn near the barrel diameter Do. Once the thickness ΔD is determined, there is almost no need to change the settings each time. Furthermore, in putting the above principle into practical use, it can be easily configured with simple adders and comparators without using technically complex multipliers and dividers used in ordinary winding diameter detectors. This is a feature of the present invention.

Structure of the Embodiment Next, an embodiment of the present invention will be specifically described based on FIG. 2.

Here too, the same parts as in FIG. 1 already described are designated by the same reference numerals. In FIG. 2, two preset counters 7 and 8 are provided. One preset counter 7 is preset with a value corresponding to the number of pulses N as a reference value. This preset counter 7 has addition and comparison functions, and outputs a reset signal A to the preset counter 8 every time the number of input pulses reaches a preset value. That is, each time the integrated value of the pulse generator 5 reaches the number of pulses N (preset value), a reset signal A is output to the preset counter 8.

On the other hand, the preset counter 8 calculates the pulse difference Δn corresponding to the minute thickness ΔD of the remaining yarn, and calculates the pulse difference Δn (no-
Δn) as a preset value. The preset counter 8 causes the input pulse count value to be cleared to "0" by the reset signal A, and generates a stop signal B when the input pulse integrated value exceeds the preset value.

Effects of the Embodiment Next, the effects will be specifically explained based on FIG. 3.

FIG. 3 is a graph showing temporal changes in the pulse counts of the preset counters 7 and 8, with time on the horizontal axis and number of pulses on the vertical axis. The dotted line indicates the count of the preset counter 8, and the dotted line indicates the count of the preset counter 8. A and B below the graph indicate generation of reset signal A and stop signal B. In addition,
In this embodiment, it is assumed that preset value N>preset value (no-Δn), but this relationship may be reversed.

The magnitude relationship between the count-out period T of the preset counter 7 and the count-out time t of the preset counter 8 before the stop position is set as follows.

T<t Therefore, until the stop position is approached, the preset counter 7 always counts out the preset value N first before the preset counter 8 counts out the preset value (no-Δn). The preset counter 8 receives a reset signal A.
are reset one after another before the countout is reached, and no stop signal B is generated.

However, when it reaches the stop position, the pulse generator 6
As the frequency of pulse generation increases, the magnitude relationship between countouts T and t is reversed and T>t. ),
It enters a count-out state and generates stop signal B.

In this way, the two preset counters 7, 8
The stop timing can be determined from the point in time when the countout periods T and t are reversed on the time axis.

Other Embodiments of the Invention The preset counters 7 and 8 in the above embodiment are both of the up type, but may also be of the down type, and may be configured not only electrically but mechanically. , or may be of a type that generates electrical signals through contacts or the like.

Effects of the invention Since the present invention can be configured with a general-purpose pulse generator and a standard presettable counter, the runout prevention device can be provided at low cost.
Moreover, since the preset can be easily performed, the handling and operation are simple.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the principle of the present invention, and FIG. 2 is a block diagram of the runout prevention device of the present invention. FIG. 3 is a graph during operation. 1... Thread sheet, 2... Barrel, 3... Beam, 4... Roller, 5, 6... Pulse generator,
7, 8...Preset counter.

Claims (1)

[Scope of utility model registration request] A pulse generator 6 is connected to the beam 3 on the drawer side of the yarn sheet 1 and generates pulses proportional to the rotation of the beam 3, and a pulse generator 6 is connected to the guide roller 4 of the yarn sheet 1 and generates pulses proportional to the rotation of the roller 4. a preset counter 8 which counts the number of pulses from the pulse generator 6 and issues a stop signal when the preset value is reached; The preset counter 7 is equipped with a preset counter 7 that issues a reset signal to the preset counter 8, and the count-out period t of the preset counter 8 before the stop position is set longer than the count-out period T of the preset counter 7 before the stop position. However, when the winding diameter of the beam 3 reaches the vicinity of the stop position, the lengths of the count-out periods T and t of the respective preset counters 7 and 8 are reversed, and the count-out period t of the preset counter 8 is preset. A run-out prevention device when pulling out a sheet-shaped bobbin beam, characterized in that the count-out period T of the set counter 7 is set shorter than that of the set counter 7.